Why was derringers nerfed?

[BaneOfGiygas]

But here's the thing: Yes, the derringer is a really powerful weapon, but it's effectively disposable. Two shots and that's your lot. Microbombs and pipe bombs are of similar cost to the derringer, are also single-use, but also pack a helluva lot of punch. Hell, a well-timed microbomb explosion lets you gib multiple people if you position yourself accordingly.